Originally, almost all windows available for use in residential applications were of the guillotine type wherein the window has a fixed upper window portion and a moveable lower window portion or alternatively, the upper window portion was the moveable portion. Still further, some windows have been built such that both upper and lower portions are moveable.
Most guillotine type windows operate such that the lower window portion is lifted and retained in the desired position by means of friction. On occasion, various types of retaining members were inserted below the open window to maintain it at the desired height.
More recently, the window industry has moved to offer many different styles of windows having different operating mechanisms for opening of the same. One of the more popular types is the casement window wherein the window is hinged at a vertical side and thus opens at the other vertical side. Advantages of this window include the ability to open the same during inclement weather. The window, as aforementioned, can be hinged at either side and thus if the hinge side is closest to the direction the wind is blowing from, it can safely be opened a certain amount to provide ventilation.
As is the case with the windows, there are now many more choices as far as operating hardware is concerned. Originally, most of the devices for opening the windows have comprised a crank operated handle which operates to move an arm outwardly, and which arm has a distal end thereof seated within a channel on the window. While there are many variations of this particular arrangement, most of them are relatively minor and the system is widely used and is an accepted standard in the industry. Most of these components are formed of metallic material and must be assembled together.
In U.S. Pat. No. 6,076,304 the teachings of which are hereby incorporated by reference, there is taught a novel window opening and closing assembly which utilizes a rack slidably mounted in a housing, the rack being moveable between first and second positions, a pinion being operatively engaged with the slidable rack and with a handle having a shaft connected to the pinion such that the pinion will move along the rack within the housing and cause the opening and closing of the window.
An advantage of the above system is that it is very compact and presents an esthetically pleasing appearance. However, it is relatively expensive to manufacture and although there is a detente formed on the shaft of the handle there is no positive locking of the device in open or closed positions.